Recombinant Lactobacillus casei Expressing Capsid Protein VP60 can Serve as Vaccine Against Rabbit Hemorrhagic Disease Virus in Rabbits

Wang, Li; Xia, Tian; Guo, Tiantian; Ru, Yi; Jiang, Yanping; Cui, Wen; Zhou, Han; Qiao, Xinyuan; Tang, Lijie; Xu, Yigang; Li, Yijing

Antigens are key factors in vaccine development. Previous studies have shown that capsid protein VP60(VP1), a major immunogenic protein of RHDV, induces expression of a neutralizing antibody [41] . Rabbits inoculated with a sufficient amount of recombinant VP60(VP1) are fully protected from wild-type RHDV, and VP60 is commonly used to develop recombinant engineered vaccines against RHDV [41, 42] . Therefore, VP60(VP1) was selected as an immunogen for the development of a recombinant engineered vaccine in this study. Recombinant engineered vaccines containing VP60(VP1) have been developed using bacteria, yeasts, plants, poxvirus-based vectors, and insect cells as delivery vectors [41, [43] [44] [45] . However, intramuscular injection, which is the main route of administering these recombinant engineered vaccines, requires trained personnel, generates a vast amount of biohazardous waste, and can elicit a stress response in the animals [18, 46] . These issues can be readily solved by live vector-based oral vaccines [18] .